A next-generation sustainable foam is a finalist in the 2017 SPE Automotive design competition.

Weight and costs are cut with castor oil foam. (SPE Automotive)

A castor oil-based foam is used in an innovative way on the 2018 Ford Fusion sedan. The material is BASF’s Elastoflex 13/4 Iso polyurethane. It’s a foam-in-place material that provides for a lower molded density and ability to be foamed in as little as 4 mm cross sections with superior bond strength to mating materials, according to Ford.

A cast PVC, TPE, or TPU skin is placed in the mold with a hard plastic retainer and the foam is injected between them. A weight savings of 20 to 40 percent (depending on foam thickness) and a cost savings of $2 per instrument panel is said to be achieved.

Use of castor oil in foam at Ford dates to 2012.

It’s part of a 17-year Ford effort to replace fossil fuels with sustainable materials led by Debbie Mielewski, senior technical leader, Materials Sustainability.

Use of material from soy and castor plants is one aspect. In another, efforts to replace glass fiber and talc with sustainable materials continues to grow. Materials under study (including a few limited commercial programs) include wheat straw, kenaf fiber, cellulose, wood, coconut fiber and rice hulls.

“There are about 400 pounds of plastic on a typical car,” says Mielewski. “Our job is to find the right place for a green composite like this to help our impact on the planet. It is work that I’m really proud of, and it could have broad impact across numerous industries.”

One of the more interesting and most recent efforts is with Jose Cuervo to find an automotive application for waste fiber from the agave plants used to make tequila.

Soy replaces oil in Ford slap pad. (SPE Automotive)

Her research team did pioneering work—with financial help from a farmers’ trade group—to make soybeans fit for use as a component in polyurethane foam now widely used in Ford cars. Soy oil is used in seat cushions, seat backs and headrests of every vehicle Ford builds in North America.

“Now, 18.5 million-plus vehicles and half a trillion soybeans later, we’ve saved more than 228 million pounds of carbon dioxide from entering the atmosphere,” says Mielewski. “This is the same amount that would be consumed by 4 million trees per year, according to North Carolina State University.”

Ford continues to collaborate with the United Soybean Board to develop soy-based materials for rubber components like gaskets, seals and wiper blades.

Ford is replacing up to 40 percent pf the petroleum in a slap pad from natural rubber in another innovation recognized as a finalist in this year’s SPE Automotive design competition. The part in the 2018 F-150 pickup and the technology can be translated to any vehicle line with leaf springs including trucks, vans and SUVs. The compression molded part is made by Rasini.

Benefits include durability and reduced noise.

Ford is also exploring innovative uses of carbon itself, and says it is one of the first in the industry to develop foams and plastics using captured carbon dioxide.

Ford is using a reinforced polypropylene made from recycled carbon fiber in the 2018 Explorer sport-utility vehicle (SUV) for the rigid portion of an “A” pillar bracket.

The material can be used with existing tooling and is compatible with thermoplastic elastomer (TPE), a new soft material for the application. Significant improvements in coefficient of linear thermal expansion are achieved, according to Ford engineers. The carbon fiber is recycled from airplane bodies, bicycles, and other sources.

The new hard/soft material system is described as more cost-effective for carbon fiber-based applications on exterior and interior trim parts. This new material usage resulted in a 14 percent component weight reduction and $186,000 annual savings.

The part is made by the Windsor Mold Group and the carbon composite is Borealis Fibermod CB061SY PP. The previous rigid material was ASA.

BASF is leading an $8 million financing for a Boston startup that says it has invented a plastic additive that is highly resistant to water.

NBD Nanotechnologies uses functionalized fluoro polyhedral oligomeric silsesquioxane (“F-POSS”) molecules as additives to polymers for providing hydrophobic and oleophobic properties. Loadings are around 5 percent and NBD claims the additive does not change the properties of the host resin.

The additive is said to possess high thermal stability for compounding and injection molding.

NBD stands for “Namib Beetle Design” because the technology was inspired by the Namib Desert Beetle, an insect that is able to harvest fog in the African desert by alternating hydrophobic and hydrophilic regimes on its back. The company was founded five years ago by two biology majors at Boston College.

Leading the plastic additive technology development at NBD is Cheng Diao, who received his Ph.D. from the University of Connecticut, Materials Science and Engineering Program in 2015, focusing on development of biodegradable polymer and composites.

The first in NBD Nano’s line of RepelShell products was introduced last year. “NBD Nano RepelShell is unlike any solution on the market because it delivers thermal stability and high surface performance through an injection-grade solution that gets added directly to the plastic,” said Deckard Sorensen, president of NBD Nano. “Imagine a professional soccer star playing on a super-muddy pitch – if the bottoms of the player’s cleats have RepelShell for Plastic, they will remain permanently and completely mud-free. The NBD additive provides end-product properties that are simply not possible with existing coatings or plastics.”

BASF is joined in the financing round by new investor Henkel AG & Co., along with existing investors including Phoenix Venture Partners.

“NBD Nano’s products allow for a tremendous variety of applications in electronics, consumer goods, and automotive,” said Markus Solibieda, managing director at BASF Venture Capital. “In addition, the company’s technology platform provides them with a strong base for future innovations.”

NBD Nano has also developed InvisiPrint coatings that reduce fingerprint visibility on a variety of surfaces.

The torque tube housing in the 2017 aluminum-bodied Mercedes GT R sports car is made from aviation-grade carbon fiber reinforced plastic (CFRP) in a one-shot production process.

The CFRP tubular shell with heavily loaded connecting flanges that replaces weight-optimized aluminum weighs 30.6 pounds, a 40 percent reduction. It allows a highly direct as well as extremely flexurally resistant and torsionally stiff transaxle-type connection between engine and transmission. The tube and the drive shaft, which is also made of CFRP can easily handle the huge torque of 700 Nm from the 585 hp Mercedes AMG-GT R, according to Mercedes-Benz engineers.

“The torque tube not only absorbs the high forces and torque during vehicle operation, but can also withstand the dynamic load cycles and peak loads that come with a sporty driving style,” the company said.

The component, finalist in the SPE Automotive design competition, was developed by Mercedes AMG with the materials specialists from Daimler Research and the fiber-composite supplier ACE GmbH. The resin is Huntsman 8625 epoxy.

According to the SPE, the part was produced with a new process (first time in auto industry) that is a combination of resin transfer molding and a process from blow molding flexible tubes. The component was inflated in the interior of the tool by vacuum and overpressure. The injection from the resin takes place from the outside.

Steam-assisted molding is taking on physical and chemical foaming as a preferred way to lightweight automotive components.

The technology is already well established in Asia to make parts for consumer electronics, such as television frames.

For example, there are more than 500 installations globally of Yudo Sun’s Rapid Isolation Cooling & Heating – (RICH) Steam Heating Technology. Major customers include Samsung and LG electronics.

Yudo has an integrated Steam Generator (Electric Boiler System) that can produce saturated steam at pressures of up to 25 BarG giving a Maximum Steam Temperature of 225 Celsius (437F)

It’s a variation of “heat/cool” that involves bringing the mold cavity surface temperature close to the plastic melt temperature to improve the component surface aesthetics. The mold is heated by flowing steam through channels located close to the cavity surface. Steam is replaced with chilled water in the same mold channels to cool the mold.

A new generation of RICH Equipment was launched last year in which (on the larger models – RICH5–R and RICH7-R) the Reverse Osmosis Water Treatment System is integrated into the main cabinet with steam generation and control equipment. A heat exchanger was incorporated to utilize the energy from steam coming back from the mold tool..

Raymond Foad, a UK representative of the technology, tells The Molding Blog that development efforts are focusing on automotive components that can be lightweighted. That’s an area where foaming technologies such as MuCell have been making headway. Foad claims that the steam-assisted approach can achieve a better surface finish.

He says there are also process advantages: “Reducing the wall section of a plastic part typically increases the plastic filling pressure significantly however, with RICH technology, the retardation of the instantaneous frozen skin layer can result in filling pressure reductions of over 50 percent.”

There are no royalty requirements, a lesson Foad learned from the gas-assist business.

The RICH system is not being used now in series production in the United States or Canada. Trials are under way, however.

There are several suppliers of steam heating auxiliary equipment in Asia.

Years of research into improving the wear resistance properties of polyamide 46 is starting to yield major dividends for DSM as auto manufacturers accelerate replacement of polyamide 66 used in chain driven valve timing systems in new turbocharged engines.

New formulation Stanyl HGR1 polyamide 46-based material was used in the launch of a new version of the Pentastar V6 engine, developed by Fiat Chrysler, DSM announced last year.

“By substituting PA66 with Stanyl HGR1 in the timing systems chain contact surfaces, frictional torque can be cut by 0.65 Nm,” said Bill Burnham, DSM business development manager. “This equates to a fuel efficiency improvement of over a mile per gallon (over 0.4 km/L) over the drive cycle; that’s a substantial amount!” In comparison to PA66, Stanyl HGR1 delivered 10% lower frictional torque within the critical engine speed range between 650 and 1800 rpm.”

Now a new improved grade designated Stanyl HGR2 is being rolled out by Ford in truck and series car production models, including the Fiesta. A friction reduction of 20 to 40 percent yields a 1 percent improvement in fuel economy, according to DSM. Testing was done by BorgWarner on Ford’s engine timing drive and valve train.

Nissan, Suzuki, and other OEMs are also using Stanyl HGR2 in new engine designs. The price premium of HGR2 is repaid in a year by fuel savings, said DSM.

General Motors is developing new hard-facing approaches using titanium and titanium carbide as it bids to expand the use of low-cost tooling made from aluminum or plastic composites for automotive parts.

The new technology is designed to expand the life of molds made from softer materials than tool steel. A benchmark of one million parts’ lifetime is often cited although GM makes no claims in a new patent on the lifetime of tools made with its hard-cladding system.

In the new GM approach, a part-forming cavity is first machined in an aluminum-nickel alloy substrate. After oxidation is removed, the substrate is hard-faced with a laser working on metallic material. The coating is machined and polished deposited in powder or wire form. The coating is machined and polished.

The purpose of the cladding is to improve corrosion resistance, wear resistance, and thermal conductivity. The range of hardness achieved is 400 kg/mm2 to about 600 kg/mm2. Hardened tool steel readings are around 550 kg/mm2.

Efforts to expand use of aluminum tooling for automotive parts have been expanding since breakthrough work by Honda about a dozen years ago. GM launched a part for its Volt electric car made in an aluminum tool in 2011.

The work on advanced aluminum tooling fits hand in glove with GM’s efforts to dramatically expand its fleet of electric vehicles, which generally have shorter production runs than current models and require innovative methods to reduce costs.

The lead inventor on the GM patent issued yesterday is Julien Mourou, who is lead engineer – Advanced Vehicle Development at General Motors. His specialty is upper exterior trim.

Patent illustration shows GM’s hard-facing approach. The laser beam is 18; the aluminum substrate is 12; and the coating is 22. (USPTO)

Posted onOctober 17, 2017byDoug Smock | PermalinkComments Off on Micro Extruder for 3D Printing Could Debut Early Next Year

A newly developed micro extruder that could be a game changer for the 3D printing business could be on the market early next year, inventor and veteran screw designer Tim Womer said in an interview this morning with The Molding Blog.

A prototype machine is now being built for an undisclosed 3D printing manufacturer and if testing progresses as planned, the machines could be offered on the market as part of a 3D printing package very soon, Womer said.

The invention overcomes inefficiencies of filament-based 3D printing that have kept the much-hyped technology from achieving its potential as a tool for series industrial production. The process is slow and expensive because of the cost of preparing the filaments.

In Womer’s invention, standard plastic pellets are fed into the micro extruder, which continuously feeds a filament-like stream into a printing head at a rate up to 20 pounds per hour. The micro extruder can be operated off a wall outlet and could find a role with hobbyists as well as industrial users.

It’s the first of its kind.

“We did a really thorough patent search and we were really surprised that no one has done this before,” Womer said in the interview. Arburg, a builder of injection molding machinery, developed a 3D printer using standard pellets called the FreeFormer. Its 3D printer, which is unique, is fed by an injection barrel and is not continuous. The FreeFormer is very expensive and is for high-end users.

The promise of Womer’s invention is that it brings the economics of extrusion to the standard 3D printing process. Womer has been designing screws and working on the extrusion process since the 1970s and has had top technical position at some of the leading companies in the business.

He is also no stranger to 3D printing. He developed the extruders that Cincinnati Inc. uses for its Big Area Additive Manufacturing (BAAM) machinery.

Womer feels the sweet spot for his machine will be production of parts that are up to a cubic yard in size—and that takes in a big chunk of industrial manufacturing. Targets will be parts that require intricate detail and tight tolerances. Even internal geometries can be easily made with 3D printers.

Speeds of 3D printers still have limitations, but research is underway to significantly improve speeds. Womer’s machine means the plastic supply can easily keep up with the printer. Plus the resin economics are much better and the plastic will not have the additional heat history of filaments.

He hopes to have at least a couple of the micro extruders on display at NPE2018 in Orlando, Florida.

Prices for recycled plastic have caved because of China’s planned exit from the marketplace. Prices for bulk rigid scrap have plunged this year from 9 cents per pound to 2.5 cents per pound, according to plasticsmarkets.org, an online marketplace for recycled plastics.

China published plans to end scrap imports by the end of this year. Licenses of plastics scrap importers were already being pulled at the time of the announcement. According to an article in the Wall Street Journal, China wants to force its plastics scrap buyers to use domestic supplies, which are growing. Close to half of America plastic scrap had been consumed by China until this year.

The screws began to tighten in four years ago when the Chinese government began to strictly enforce regulations on non-conforming materials in imported recycled paper and plastics as well as restricting the import of certain other plastic recyclables.

The situation creates a conundrum for environmental movements in the United States.

Recycling by American municipalities has tripled in the last 25 years. The commercial value of post-consumer plastic, considering cleaning and logistics costs, is moving closer to null. It could be diverted to waste-to-energy plants, but that approach is not popular with environmentalists. Landfilling is no longer an option in most areas. Increased use of recycled content in American manufactured goods is an option, but a very slow process.

Veteran screw designed Tim Womer has developed a single-screw micro extruder to improve the cost effectiveness of 3D printing. A U.S. patent application for the technology was published today.

In Womer’s invention, a rotatable screw is attached to a torque drive of the printer, and extends through the feed chamber and conical bore of the barrel. The channel root depth at the exit opening of the extrusion barrel is about 0.025 to 0.075 inches.

Womer said the design uses standard pellets and specifically addresses challenges of 3D printers, which currently use filaments of plastic made from pellets. One immediate advantage is that the plastic won’t have the additional heat history in Womer’s concept.

“With the growth of 3D printing, an opportunity has been created to invent and develop a relatively small extruder, appropriately scaled to size that can deliver a consistently uniform and repeatable flow of molten plastic to a printer head at a rate of 20 lbs per hour or less,” Womer states in the patent application.

In 3D printing, the extruder must be able to operate at screw speeds from 0 to 400 rpm. Different screw designed are used for different plastics.

Womer’s invention overcomes many limitations of the filaments used in 3D printers. First filaments must have uniform composition and dimension or deposit rates will vary from spool to spool. Filaments may also break, slowing production. Spool costs are high and not all thermoplastic resins are available in filament form. Womer sates: “In summary, spool driven 3D printers are slow, failure prone, labor intensive, expensive to operate, and limited to particular polymer resins.”

Womer’s invention is part of a trend to make 3D printing more production friendly. 3D printing was developed as a way to make prototypes rapidly.

A former president of the Society of Plastics Engineers, Womer was the Global Corporate Technical Advisor for Xaloy, and has also served in leadership positions in engineering, research and development at Spirex, Conair, and NRM. He started a consulting business in Edinburg, Pennsylvania in 2011.